#### Heat Book Back Questions

6th Standard

Reg.No. :
•
•
•
•
•
•

Science

Time : 00:45:00 Hrs
Total Marks : 30
3 x 1 = 3
1. When an object is heated, the molecules that make up the object

(a)

begin to move faster

(b)

lose energy

(c)

become heavier

(d)

become lighter

2. One litre of water at 30o C is mixed with one litre of water at 50o C. The temperature of the mixture will be

(a)

80o C

(b)

More than 50°C but less than 80o C

(c)

20o C

(d)

around 40o C

3. An iron ball at 50°C is dropped in a mug containing water at 50o C. The heat will

(a)

flow from iron ball to water.

(b)

not flow from iron ball to water or from water to iron ball.

(c)

flow from water to iron ball.

(d)

increase the temperature of both.

4. 3 x 1 = 3
5. The SI unit of temperature is ___________________.

()

kelvin

6. Solids________________ on heating and______________ on cooling.

()

expand, contract

7. Two bodies are said to be in the state of thermal______________ if there is no transfer of heat taking place.

()

equilibrium

8. 2 x 1 = 2
9. Borosilicate glass do not expand much on being heated.

(a) True
(b) False
10. The unit of heat and temperature are the same.

(a) True
(b) False
11. 3 x 2 = 6
12. What is temperature?

13. What is thermal expansion?

14. What do you understand by thermal equilibrium?

15. 2 x 3 = 6
16. What difference do you think heating the solid will make in their molecules ?

17. Distinguish between heat and temperature.

18. 2 x 5 = 10
19. Explain thermal expansion with suitable examples.

20. Suppose your normal body temperature were lower than what it is. How would the sensation of hot and cold change?